light up

phrasal verb

1

of a light : to become lit : to begin shining

All of the lights on the display suddenly lit up.

—often used figuratively to express interest or pleasure

His eyes/face lit up when she walked in the room.

2

informal, of a telephone : to show a light indicating that someone is calling

When the DJ announced a contest, the phones lit up.

3

informal : to light a cigarette

I can't wait to light up after work.

Examples of light up in a Sentence

Recent Examples on the Web

These storms trigger interactions between the Earth’s magnetic field and charged particles from the sun, resulting in the stunning colors that light up the sky. —Valerie Mesa, People.com, 1 Sep. 2025

The northern lights could light up the skies across several parts of the United States on Monday due to a geomagnetic storm, according to space and weather experts. —Megan Forrester, ABC News, 1 Sep. 2025

In the fall, its 318 woodland acres light up with some of the most beautiful foliage in the area. —Caroline Rogers, Southern Living, 31 Aug. 2025

Social feeds light up with memes, debates, and highlight reels. —Abdo Riani, Forbes.com, 31 Aug. 2025

Rhymes for light up

• backup
• blowup
• breakup
• buildup
• checkup
• cleanup
• holdup
• hookup
• lineup
• lockup
• makeup
• markup